Rotary pump



June 1o, wm. 1,497,050

G. WARDWELL 1 ,gonny PUMP Filed' oci. 25', 1923 s sheets-sneer .1

,amr-15mm?! `June 10,1924@ G. w. WARDWELL l June l0 392%.' 1,497,050

l G. w. WARDWELL ROTARY PUMP lFiled voct. '25, 1923 s sheets-sheet 5 INVENTOR A TTORNEY pump vthat GEORGE W. WABDWELL, OFSOUTH COMPRESSOR & UMP COMPANY, WARE.

NORWALK, CONNECTICUT, ASSIG-NOIB: '.lO THE HEL 0F NEW YORK, N. Y., A CORPORATION OF IJIEIIA ROTARY PUMP.

Application le October 25, 1923.- Serial No. 670,686.

To all whom it may concern:

Be it known that I, GEORGE W. WAID.- WELL,`a citizen of the -United States, residing at South Norwalk, in the county of Fairfield and State of Connecticut, have 1nvented a new and useful Improvement in Rotary Pumps, of which the following isa speciiication. v v

This invention relates to rotary pumps of 'the type having an internally toothed drive ing gear engaging with anI externally tootheddriven gear of a diierent number of' teeth, for pumpingv and compressing iuids, more particularly gases. l

The object of the invention is to provide a very simple means whereby the pressure accumulated by the pump E for keeping the working joints sealed and lubricated. I 'l This object is attained by fitting the rotor, which contains and actuates the co-operating gears, so that it `will loat axially in the pumping chamber, and providing spring means that initially push the rotor and gears against the end of the pumping chamber, said means' being located in a cavity that is .connected to receive sure, and so arranged as to retain discharge pressure back of the rotor in such manner that the pressure will effect the operating .seal supplemental to the initial seal caused vby the spring means.

In the` accompanying drawings Fig. 1 shows a central longitudinal section of a embodies the invention. Fig. 2 shows a face view' of the pump ywith the head removed. section on the planeindicated by the dotted line 3-3 on Fig. 1.. Fig. 4 shows a modified form of spring sealing means. Fig. 5 shows another modification. f

The casing 1 whi in sectional outline, contains a cylindrical pumping chamber 42 that is closed on one end by a head 3 which isfastened to the casing by any suitable means. The casing has an intake passage 4 on one side and a ydischarge passage 5 on the other side while the head has an intake port 6 leading from the intake passage to the pumping chamber and a-discharge port 7 leading from the pumping chamber to the discharge passage.

Rotatably fitting and having a slight movement axially in the pumping chamber is a rotor A8. The hub 9 of the rotor is may be utilized discharge pres- Fig. 3 shows a-transverse h is generally circularA mountedon anti-friction bearings 10. The driving shaft 11 is splined in the hub of the rotor so rotor it will not interfere with the axial movement oim the rotor.

Fastened to the rotor is an internally. toothed gear 12 and engaging the teeth of this gear are the teeth of an externally toothed gear 13. The externally toothed gear-is mounted on anti-friction bearings 14 the head. rlhe stud is positioned 4out of line with the driving shaft so that the axis of the externally toothed gear'will be eccentric to the axis of theinternally toothed gear. One of these Agears has more teeth than the other and they coact ina well' known manner to eect the pumping or compression of iiuids. v

n a' cavity 16 that 'communicates with the pumping chamber and fastened gas-tight against the end of the hub of the rotor is a diaphragm 17 which is somewhat elastic, and thrusting between this diaphragm and the inner race ring 18 of the anti-friction bearing is a conical spring 19. Secured to' the back of the diaphragm is a hardened in a hardened ring 21 that is tightly set in the end of the cavity that contains the antifriction bearing, spring .and diaphragm. This cavity communicates with the pumping chamber back of the rotor and is connected by a pipe 22 with the discharge rom the pump or the reservoir to which the discharge leads, so that discharge pressure ac-' cumulated by the pump will be exerted in the cavity. L bricant is placed in this cavity.. e

The tension of the diaphragm forces the rotor forward and' presses the rotor and vcontained gears against the inner'ace of the head so that under low pressure, as'on the stapt of the pump,

e As the pump accumulates pressure its force is exerted in the chamber'in such manner that i-t presses the diaphragm back causing the rings to seat tightly' and at the same time mi? 4face of the head and eect a sealing proportional to the degree of pressure. As the rings are that while the shaft will turn the thatare supported by a stud 15 'fastened in the pumped fluid will B0@ lnot leak across the faces of the'gears.

forced together by the accumulated El@ hub, is corrugated in order that it may have sufiicient spring to effect the initial sealing. `When made in this way it is unnecessary-to employ the Spiral spring, for the tension of the corrugated diaphragm keeps the joint between the rings tight and the joint between the gears and the face of the head tight and permits the discharge pressure to accumulate sufficiently to eifect the tight sealing which is required to render the pump efficient. Such lubricant as is forced by the pressure between ther v wearing surfaces will pass out of the pump and drain backto the pressure chamber.

ln the form shown in Fig. 5 the diaphragm is, instead of being fastened directly tothe hub of the rotor as in the two forms described, fastened to a sleeve 26 which is keyed to the shaft but has a longitudinal movement in a recess 27 in the hub of the rotor. With this construction the spring normally tendsto separate the diaphragm and the rotor so as to keep the parts sealed under the initial tension.

l. A. rotary pump comprising a casing containing a pumping chamber and a pressure cavity communicating with the pumping chamber, a rotor rotatable in and having an axial movement in said chamber, means actuated by said rotor for pumping fluid, a vyielding diaphragm in the pressure cavity, said diaphragm having a Huid-tight vconnection with the rotor and closing one end of the cavity, and means forconducting pressure accumulated by the pump to the pressure cavity, between the diaphragm and the back of the rotor. s

2. A rotary pump comprising a casing containing a pumping 'chamber and a pressure cavity communicating with the pump-A ing chamber, a rotor rotatable in and having an axial movement in said chamber, internally-toothed and externally toothed intermeshing gears actuated by said rotor for pumping fluid` a yielding diaphra in the pressure cavity, said diaphragm aving a Huid-tight connection .with the rotorv and closing one end of the cavity, and means forconducting pressure accumulated by the pump to the pressure cavity, between the vdiaphragm and the back of the rotor.'

3. A rotary pump comprising a casing containing a pumpingchamber and a pressure cavity communicatingvwith the umpj 111g chamber, a rotor rotatable in an having an. axial movement jinv -said chamber, means actuated by said rotor for 'pump-ing 'lliuid, a diaphrathe pressure cavity Leaves@ Y means actuated by said rotor forfpumping Vfluid, a diaphragm in the pressure cavity fixed Afluid-tight to the rotor, a'ring .fixed to the back of said diaphragmenga'ging a ringin the end of the pressure cavity, and means for conducting pressure accumulated by the pump to the pressure cavity, between the diaphragm and the back of the rotor.

5. A rot-ary pump comprising a casing containing a pumping chamber and a pressure cavity communicating with the pumping chamber, a rotor rotatable in and having an 'axial movement in said chamber, means actuated by said rotor i'or pumping fluid, a diaphragm in the pressure cavity vfixed Huid-tight to the rotor, a ring Hired to the back of said diaphragm engaging a ring in the endY of Ythe pressure cavity, a Vspring in the pressure'cavity andpthrustingbetween the diaphra and the, rotor, Yand means for conducting pressure accumulated by the pump to the pressure cavity, between the diaphragm and vthe back ot the rotor. f-

6. A rotary pump comprising a casing containing a pumping chamber and apressure cavity communicating with the pumping chamber, a rotor rotatable vin and having an axial movement in said chamber, means actuated by saidrotor for pumping duid', a corrugated diaphragm in the pressure cavity '.ixed fluid-tight to the rotor andclosing one end of the cavity, and means-tor conducting pressure accumulated by the pump to the `chamber and thrustin .between t e Ydiaphragm and the rotorJ earings, and means for conducting pressure accumulated by the pum to the ressure cavity, between the diap ra an the back of the rotor.,-

8. A. rotary pump .ccmprising 'a'casing ice by said rotor for pumping naamw,

containing. a pumping chamber 'and a pres- 4 sure cavity communicating with the pumping chamber, a rotor rotatable in and having VanV axial movement in said chamber, means 5 actuated by said -rotorfor'pumpmg fluid, a

10 accumulated by the pump t9 the' pressure cavity, betweenthe diaphragm andthe back o the rotore A s 9.. rotary pump comprising a casing Y 'containing a pumping chamber and a pressure cavity communicatingwith the umping chamber, a rotor rotatable in an hav.- ing an -axial movement in said chamber, means actuated by said rotor for pumping Huid, a driving shaft, a sleeve keyed to the shaft so vas to'. rotate `therewith but have a longitudinal movement thereon, a diaphragm in the pressure cavity xed Huid-l tight to said sleeve and closing one end ofthe c nd means for conducting pressure cavity, accumu ated by the pump to the pressure cavity between the diaphragm and 'the' back of the rotor.

' GEORGE 'W. WARDWELL. 

